1. Field of the Invention
The present invention relates to an endoscope in which a head unit including a visualizing means is freely detachably attached to the distal end of an inserting unit main body thereof.
2. Description of the Related Art
Endoscope systems have been widely used in the past, wherein an elongated inserting unit of an endoscope is inserted into a body cavity in order to observe an intracavitary organ or to, if necessary, perform various therapeutic procedures using a treatment instrument passed through a treatment channel.
In recent years, a technology for electronic endoscopes has been proposed in, for example, Japanese Patent No. 2966723. According to the technology, an electronic endoscope includes an image pickup unit that is detachable from an endoscope main body. When the endoscope reaches an intended lesion, the image pickup unit incorporated in the distal portion of the endoscope is detached for visualization of the lesion.
According to other conventional electronic endoscope technology, pressure deriving from a jet of fluid is used to cancel magnetic force with which the image pickup unit is fixed to the distal portion of the endoscope so that the image pickup unit can reach an appropriate position in the lesion. Otherwise, a self-propelled means or a self-position collecting means such as a flagellum driver or a caterpillar driver is adapted to the image pickup unit.
Moreover, the image pickup unit is restored to the distal portion of the endoscope using magnetic force generated by an electromagnet or using the self-propelled means or self-position correcting means.
Moreover, as other conventional electronic endoscope technology, a technology according to which a visualizing means is, in addition to an image pickup unit detachable from an endoscope main body, incorporated in the endoscope main body has been proposed in, for example, Japanese Patent No. 2969042.
Furthermore, as other conventional electronic endoscope technology, a mechanism that includes a wire linking an image pickup unit and an endoscope main body and that restores the image pickup unit to a distal portion of the endoscope when the wire is pulled has been proposed in, for example, Japanese Patent No. 2969043.